Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 69c202af authored by Andrea Paterniani's avatar Andrea Paterniani Committed by Linus Torvalds
Browse files

[PATCH] SPI: Freescale iMX SPI controller driver (BIS+)



Add the SPI controller driver for Freescale i.MX(S/L/1).
Main features summary:

 > Per chip setup via board specific code and/or protocol driver.
 > Per transfer setup.
 > PIO transfers.
 > DMA transfers.
 > Managing of NULL tx / rx buffer for rd only / wr only transfers.

This patch replace patch-2.6.20-rc4-spi_imx with the following changes:
 > Few cosmetic changes.
 > Function map_dma_buffers now return 0 for success and -1 for failure.
 > Solved a bug inside spi_imx_probe function (wrong error path).
 > Solved a bug inside setup function (bad undo setup for max_speed_hz).
 > For read-only transfers, always write zero bytes.

This is almost the same as the 'BIS' version sent by Andrea, except for
updating the 'DUMMY' byte so that read-only transfers shift out zeroes.
That part of the API changed recently, since some half duplex peripheral
chips require that semantic.

Signed-off-by: default avatarAndrea Paterniani <a.paterniani@swapp-eng.it>
Signed-off-by: default avatarDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent fdb3c18d
Loading
Loading
Loading
Loading
+8 −0
Original line number Diff line number Diff line
@@ -75,6 +75,13 @@ config SPI_BUTTERFLY
	  inexpensive battery powered microcontroller evaluation board.
	  This same cable can be used to flash new firmware.

config SPI_IMX
	tristate "Freescale iMX SPI controller"
	depends on SPI_MASTER && ARCH_IMX && EXPERIMENTAL
	help
	  This enables using the Freescale iMX SPI controller in master
	  mode.

config SPI_MPC83xx
	tristate "Freescale MPC83xx SPI controller"
	depends on SPI_MASTER && PPC_83xx && EXPERIMENTAL
@@ -94,6 +101,7 @@ config SPI_OMAP_UWIRE
	help
	  This hooks up to the MicroWire controller on OMAP1 chips.


config SPI_PXA2XX
	tristate "PXA2xx SSP SPI master"
	depends on SPI_MASTER && ARCH_PXA && EXPERIMENTAL
+1 −0
Original line number Diff line number Diff line
@@ -13,6 +13,7 @@ obj-$(CONFIG_SPI_MASTER) += spi.o
# SPI master controller drivers (bus)
obj-$(CONFIG_SPI_BITBANG)		+= spi_bitbang.o
obj-$(CONFIG_SPI_BUTTERFLY)		+= spi_butterfly.o
obj-$(CONFIG_SPI_IMX)			+= spi_imx.o
obj-$(CONFIG_SPI_PXA2XX)		+= pxa2xx_spi.o
obj-$(CONFIG_SPI_OMAP_UWIRE)		+= omap_uwire.o
obj-$(CONFIG_SPI_MPC83xx)		+= spi_mpc83xx.o

drivers/spi/spi_imx.c

0 → 100644
+1769 −0

File added.

Preview size limit exceeded, changes collapsed.

+72 −0
Original line number Diff line number Diff line
/*
 * include/asm-arm/arch-imx/spi_imx.h
 *
 * Copyright (C) 2006 SWAPP
 *	Andrea Paterniani <a.paterniani@swapp-eng.it>
 *
 * Initial version inspired by:
 *	linux-2.6.17-rc3-mm1/include/asm-arm/arch-pxa/pxa2xx_spi.h
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

#ifndef SPI_IMX_H_
#define SPI_IMX_H_


/*-------------------------------------------------------------------------*/
/**
 * struct spi_imx_master - device.platform_data for SPI controller devices.
 * @num_chipselect: chipselects are used to distinguish individual
 *	SPI slaves, and are numbered from zero to num_chipselects - 1.
 *	each slave has a chipselect signal, but it's common that not
 *	every chipselect is connected to a slave.
 * @enable_dma: if true enables DMA driven transfers.
*/
struct spi_imx_master {
	u8 num_chipselect;
	u8 enable_dma:1;
};
/*-------------------------------------------------------------------------*/


/*-------------------------------------------------------------------------*/
/**
 * struct spi_imx_chip - spi_board_info.controller_data for SPI
 * slave devices, copied to spi_device.controller_data.
 * @enable_loopback : used for test purpouse to internally connect RX and TX
 *	sections.
 * @enable_dma : enables dma transfer (provided that controller driver has
 *	dma enabled too).
 * @ins_ss_pulse : enable /SS pulse insertion between SPI burst.
 * @bclk_wait : number of bclk waits between each bits_per_word SPI burst.
 * @cs_control : function pointer to board-specific function to assert/deassert
 *	I/O port to control HW generation of devices chip-select.
*/
struct spi_imx_chip {
	u8	enable_loopback:1;
	u8	enable_dma:1;
	u8	ins_ss_pulse:1;
	u16	bclk_wait:15;
	void (*cs_control)(u32 control);
};

/* Chip-select state */
#define SPI_CS_ASSERT			(1 << 0)
#define SPI_CS_DEASSERT			(1 << 1)
/*-------------------------------------------------------------------------*/


#endif /* SPI_IMX_H_*/